Method of forming casings



Dec. 2, 1941, 1 a EI E HAUER 2,264,627

METHOD OF FORMING CASI'NGS Filed April 18, 1938 '7 Sheets-Sheet 1 7 Sheets-Sheet 2 Snventor Dec. 2, 1941- c. B. EISENHAUER METHOD OF FORMING CAS INGS Filed April 18, 1938 D 2, 1941- c. B. EISENHAUER 226 527 METHOD OF FORMING CASINGS Filed April 18, 1938,

7 Sheets-Sheet 3 66 66 6f 66 1a {2 w m )1 A.

inventor (9/7/9155 5. flaw/mazeattorneys D86. 2, 1941. B. g sEN u R 2,264,627

METHOD OF FORMING CAS'INGS Filed April 18, 1938 7 Sheets-Sheet 4.

Dec. 2, 1941. Q ElsENHAUER. I I 2,264,627

METHQD OF FORMING CASINGS 7 Sheets-Sheet 5 Filed April 18, 1938 Zinnehtor (3 441555 Eff/W4? attorneys .Dec. 2, 1941. c. B. ElS ENHAUER 2,264,627

METHOD OF FORMING CASINGS Filed April 18, 1958 7 Sheets-Sheet 6 ISnnentor CZW/PZESE fist-M9445? Dec. 2, 1941. c. B. EISENHAUER METHOD OF FORMING CASINGS Fild April" 1 1938 7 Sheets-Sheet 7 3 n 0 en tor 5567109460519.

Patented Dec. 2, 1941 2,264,627 H METHOD or FOR-MlNG CASINGS Charles B. Eisenhauer, Detroit, Mich., assignor by mesne assignments, to Reconstruction Finance Corporation, Detroit, Mich a corporation of the United States Application April 18, 193

Claims.

This invention relates generally to a method of and apparatus for manufacturing casings and more particularly to a method of and apparatus for manufacturing casings for leaf springs.

It is an object of the present invention toprovide a new and improved method of and apparatus for manufacturing elongated longitudinally flexible leaf spring casings.

Another object of the invention is to provide a new and improved method of and apparatus for inexpensively manufacturing elongated sectionally constructed flexible spring casings. 7

Another object of the invention is to provide a new and. improved method of and apparatus for manufacturing elongated sectionally constructed spring casings which may be formed as unitary structures so that they may be easily handled.

Other objects of the invention will be apparent from the following description taken in connection with the accompanying drawings which form a part of the specification and in which 7 Figure 1 is a view shown in side elevation of an apparatus embodying my invention;

Fig. 2 is a view in cross section showing certain structural details of the present apparatus;

Fig. 3 is a front view shown in elevation taken along the line 3--3 of Fig. 1, of a plurality of guides or gauges employed in the apparatus;

Fig. 4 is a top plan view of the gauges shown in Fig. 3 and associated structure;

Fig. 5 is a View shown in'cross section of a die of the present apparatus; v

Fig. dis a top plan view of the lower die, taken along the line 6-6 of Fig. 5;

Fig. '7 is a view shownin cross section of the die taken along the line and in the direction of the arrows 'l-'! of Fig. 6, showing the die in closed position r Fig. 8 is a fragmentary viewshown in cross section of the die taken along the line 8 '8 of Fig. 6 and showing the upper die in raised position; 7

Figs. 9, 10 and. 11 are fragmentary views shown in cross section of the die showing the upper die in different positions withrespect to the work and to thelower die;

8, Serial No. 202,625

Fig. 12 is a view shown in cross section of a Figure 16 is a view of one end of a finished spring casing.

Figure 17 is a diagrammatic view illustrating the present method of preparing a sectionally constructed blank from which a spring casing may be made; and I Figure l8 is an enlarged view of one of the blanks. V

Referring to the drawings by characters of reference and. first to Fig. 1, the present apparatus includes a power press having a frame [0 including an upper base l on which is supported a bed l2 which is preferably angularly disposed,

sloping downwardly from front to rear of the apparatus. Mounted on the bed l2, adjacent the front thereof, is a die. designated in general by the numeral l3, which may be termed a stitching die and also mounted onthe bed l2 rearwardly of and adjacent to the die l3 in a shearing die I4. The power press for operating the dies [3 and [4 may be of any suitable type and may include spaced driven shafts l5 and I6 intermediate of which there may be a drive shaft ll, these shafts extending transversely of the apparatus in relatively spaced parallel relation and may be journaled for rotation in suitable bearings in frame Ill. Keyed to the drive shaft 11, a drive gear I 8 meshes with and drives similar gears 19 and Mia keyed respectively, to the driven shafts l5 and I6 and the drive shaft 11 may be driven or rotated by any suitable source of power. Keyed respectively to the driven shafts l5 and I6 are eccentrics 20 and 2| which slidably rotate in bearings or straps 22, on the lower ends of connecting rods 23 which operatively connect the eccentrics to upper movable die heads 24 and 25 respectively of the dies 13 and I4.

Positioned at the front or in advance of the stitching die I3 is a pair of feed rollers 26 and 21 for feeding a plurality of continuous, substantialy parallel stripsof metal 21a to the stitchingdie l 3 which then attaches adjacent strips togetheralong adjacent longitudinal edges thereof as will later be seen. Preferably the strip stock 21a is wound on spools 28, which may be rotatably supported by a frame 30. The feed rollers 26 and 21, of which the lower roller 26 is the drive roller, have shafts 3| and 32 respectively which are journaled in hearings in the upstanding sides 33 of a U-shaped support 34, supported and rigidly secured to an L-shaped bracket 35 which in turn is rigidly secured to the frame ll] of the power press. Keyed to the drive roller shaft 3|, a gear 36 meshes with a gear 31 which is keyed to a shaft 38 on which a second gear 39 is provided and meshes with a reciprocal gear rack which is reciprocated in accordance with operation of the dies to periodically drive the feed roller 26 in a direction to feed the strips 27a to the dies. The gear rack 40, Fig. 2, is slidably received and guided in a slideway 4| provided in a plate member 42 which may be rigidly secured to the L-shaped bracket '35 by any suitable means. The gear 39 is loosely mounted on the shaft 38 and carries a pawl 43 which cooperates with a ratchet 44 keyed to the shaft 38, to provide for intermittent rotation of the rollers 26 and 27 in one direction only. A lever 45 having one end pivoted to the gear rack 40 is pivoted intermediate its ends, as at 46, to the plate member 42 and at its other end is pivoted to one end of a connecting rod 41, the other end of which is pivoted to a lug 48 provided on the connecting rod strap 22 of the stitching die. It will be seen that on the upstroke of the press, the rack "40 will be moved toward the press, rotating the rollers 26 and 21 which will feed the metallic strips 21a to the dies and that onthe down stroke of the press feeding of the strip stock will be stopped by reason of the pawl 43 and ratchet 44.

Referring now to the detail construction ,of the stitching die |3, Figs. 5 and 6, the lower part of this die includes a base plate 55 which may be rigidly secured to the bed I2 by any suitable means and mounted on the base 50 are transverse rows of raised die plates comprising -a front row of die plates 5|, a rear row of die plates 52 and an intermediate row of die plates 53, the plates of each row being relatively spaced transverse of the apparatusor transverse to the direction of feeding of the metallic strip stock 2111. The die plates 5|, orfirst row of plates, are each provided with a punch receiving aperture 54 to receive -a single punch 55, these apertures aligning transversely of the die base at an angle to the direction of feeding of the metallic strips 21a and the rear row of die plates 52 are provided with punch receiving apertures 56 to receive a double punch 51, which apertures are relatively aligned transversely of the die base in parallel relation with the aligned apertures of the first row of die plates. The intermediate row of die plates .53 are each provided with a pair of spaced, punch receiving apertures 54a and 56a, the apertures 56a to receive single die punches 55 and the apertures 56a to receive double die punches 51, Fig. '7. The die punches 55 and 5'! are rigidly secured in blocks 6| which in turn are carried by and rigidly secured to the underside of the upper movable die head .24.

The punch receiving apertures 54c and 55a of the intermediate die plates 53 respectively, align transversely of the strips 27a ,to be attached together and alignment thereof is at an acute angle to the alignment of the front and rear rows of punch receiving apertures, the present die in one operation stitching or attaching together strips for two sectional blanks whichafter shearing by the die M are trapezoidal in form as shown in Fig. lei.

The die plates 5|, .52 and 53 are each mounted on a pair of spaced blocks 52 and may be rigidly secured thereto and to the base 50 by screws .63 or by other suitable means. A plurality of spaced, elongated movable stripper plates 54 having apertures to receive the die punches are provided and are spaced slightly and immediately above the die plates, the stripper plates 54 extending transversely of the strips 21a. Springs 6466 urge the stripper plates 64 downwardly, such movement being limited by the heads of screws 641) which are screwthreaded into the upper die base 24. A plurality of lower vertically movable stripper plates 55 are provided and extend in relative spaced relation from front to rear of the base 50 between the raised die plates, the metallic strips 21a to be attached together being supported on the upper surfaces of the movable stripper plates 65 and on the upper surfaces of die plates 5|, 52 and 53. Helical coil springs 66 urge the stripper plates 65 upwardly, upward movement .of the stripper plates 65 being limited slightly above the die plates 5|, 52, 53 by the heads of screws-Bl which arescrewthreaded into the stripper plates and have their heads movable in and adapted to engage the end walls of recesses in the fixed base 50.

A plurality of elongated longitudinally slidable cam members 59 extend one under each row of the die plates 52 and on movement raise and/or lower cam engaging or follower members 10. The cam members 59 have longitudinally spaced, laterally extending portions 1|,Fig. 7, .each providedwith an inclined upwardly facing cam surface 12, which position in spaced cutouts l3, only one of which are shown in the cam follower members 10 which have downwardly facing inclined cam surfaces 14 for cooperative engagement with the inclined surface 12. Acting against one end of each of the elongated cam members 69 are helical coil springs 15, Fig. 6,

(IDL- which act to move the cam member 59 in a direction to permit the cam follower member 10 to descend, the cam engaging member 10 being limited in such movement by stop members 1.5a rigidlysecured to the base 55. Each of the slidably movable cam members 69 is provided at the end thereof .opposite its respective spring 15 with an upwardly facing inclined portion 76 and the upper punch carrying plate carries depending members Tl provided on their lower ends with inclined surfaces [8 adapted to engage the inclined surfaces 16 to move the cam members 69 longitudinally against the action of the springs 515 to raise the cam follower members 10. Loosely supported on the upper surface of the cam follower members 10, a plurality of abutment members 19 have upwardly extending portions 19a which project into and are retained in the punch receiving apertures in the die plates 5|,

52 and 53, the upper ends of these portions 'l-Sa, on upward movement of the cam follower members 10 engaging the tabs -80 which are punched out by the die punches and crimping or bending the .tabs over thereby to attach the several strips 21a of strip stock together. Helical coil springs 8|, compressed between the underside of the die plates 5|, 52 and 53 and flanges 82 .of the abutment members 10, act to urge the abutment members downwardly maintaining them in engagement with the upper surface of the cam follower members 10. The punches as shown in Figs. 7 to 10 inclusive have a depending punch portion 83 foifset from the upwardly extending abutment portions '19 .and have a downwardly facing abutment surface 84 overlying and cooperable with the upper ends of the abutment members 19 to bend over the tabs 80, the lower end of the punch :having a downwardly facing inclined surface 85 terminating in a lower pointed end 85 for piercing the metal strips. It will be seen that the inclined surfaces 85 on the punches causes the tabs 88, formed out of metal strips, tocurl back ..and under the metal in position to be crimped or flattened by the abutment members I9 on closing of the die.

Referring now to the shearing die I4 and more particularly to Figs. 12 and 13, this die includes a fixed base 85a rigidly secured to the frame It! and mounted on' the base 85a is a pair of elongated lower shearing die members 8611 which are angularly disposed in relative tapered relation. These die members 86a are mounted on and rigidly secured to spacers 81 and to the die base 85a by screws 89. Positioned between the spaced die members 86a, a filler plate 68a has its upper surface flush with the upper surface of the die members and seats on spacers 89, the filler plate and spacers being rigidly secured together'and to the die base 85a by screws 96. The upper, outer, longitudinal edges 9I of the die members 86 are cutting edges which cooperate with lower inner cutting edges 92 of die members 93 carried by the movable die head 25, the upper cutting edges 92 being positioned outwardly of the lower cutting edges 9|. The upper die members 93 are of elongated form and are spaced from the upper die base 94 by spacers 95, the parts being rigidly secured together by screws 96. Positioned above the lower die members 81 and carried by the upper die base 94 is a stripper plate 97 which is urged downwardly by helical coil springs 96, downward movement being limited by the heads 99 of screws I66. ing dies 81, front and rear stripper plates I9I and I62 respectively are provided and are urged upwardly by helical coil springs I63 which seat in recesses in the base 85, upward movement of the stripper plates being limited by the heads I94 of screws I65 which are screwthreaded into the stripper plates and have their heads I64 movable in recesses in the lower die base 85.

Mounted on and rigidly secured to the forward ends of the stitching die lower stripper plates 65, Figs. 1 and 6, is a unitary structure I96 comprising a plurality of gauges or guides for guiding the several strips of stock 21a so that they will be fed to the dies with their adjacent longitudinal edges in overlapping relation along which overlapped edges the strips 21a are pierced and attached together at spaced intervals by the stitching die I3. The guide structure I96, Figs. 3 and 4, includes a base I68 secured to the underside of the movable stripper plates 65 transversely thereto on which is mounted and rigidly secured thereto a plurality of transversely spaced blocks I69. Angularly disposed supporting plates I I6 are each secured at their opposite ends to a pair of the blocks I69 and extend in relative spaced relation, successive plates being in relative overlapping relation. Mounted on and secured to the supporting plates H6 are spaced guide members H2 which co-operate with the blocks I69 to guide the metallic strips I61, the

guide members II2 preferably having extended portions II3 overhanging the strips II". The guide member II2 and the cooperating guide blocks I69 preferably have rounded formed ends, as at II4 to aid in starting the strip stock in the guideways. A second guide structure I66a which may be of the same construction as the guide structure I66 is preferably provided in advance of the rollers 26, 2! for aiding in guiding the continuous metallic strips so that they will be presented to the dies with their adjacent longitudinal edges in overlapping relation.

After the metallic strips ZIa have been attached together longitudinally thereof by the stitching die I3, the shearing die I4 shears the Outwardly of the lower shearcontinuous strips transversely thereof into sec tionally constructed blanks 21a, Fig. 14, which then may be easily handled in the operation of forming theminto leaf spring casings one of which is shown in Fig. 15.

The operation of the herein described appara-.

. tus'is as'follows: On raising or opening move-' ment of the dies I3 and I4, the rack 49 which is operatively connected to the connecting rod strap 22 by link 41 and lever is moved forward and through gears 39, 36 and 31 drives the'rollers 26, 21 which feed the continuous strips 21a to the dies I3 and I4, the strips 21a first passing through the guide structures I 66a and I66 which position and retain adjacent strips with their adjacent longitudinal edges in relative overlapping relation. On downward movement of the upper dies the rack 40 is moved in the opposite direction but by reason of the pawl 43 and ratchet 44, Fig. 2, the rollers 26 and 2i are not rotated and feeding of the strips is discontinued during this movement of the rack 46 to permit the dies I3 and I4 to stitch and shear respectively the strips then in the dies. On descent of the punches, Figs. 9, 10 and 11, the pointed ends thereof pierce the overlapped border portions of adjacent strips I61 and as the punches continue to descend the beveled surfaces 85 thereof cause the double thickness of metal or'tabs to curl under the strips immediately above the upper ends of the upwardly movable abutment member I9. Also as the punches descend, the movable stripper plates 65 are moved downwardly against the action of the springs 66 and the depending abutment members TI carried by the upper die base engage the inclined cam surfaces 16 of the 1ongitudinally movable cam members 69 which move the cam follower-members upward against the action of the springs l5-raising the abutment members I9 upward to flatten the tabs 89 between the upper ends of the abutment members and the downwardly facing abutment surfaces 34 of the punches 55, 51. On upward movement of the upper die or punches, the cam members 69 are released and are returned by the springs I5 which permits the cam follower members I6 and the abutment members I9 which are loosely supported on the upper horizontal cam surfaces to descend, downward'movement of the abutment members I9 being aided by the springs 8|. It will be understood that the present stitching die I3 in one operation of the die attaches strips together for two blanks each blank having along one longitudinal edge thereof spaced single tabs punched out and turned over and along and adjacent the other edge thereof a row of spaced pair of tabs, although any suitable number of tabs and arrangement thereof may be had, as desired. On raising or opening of the stitching die I3 the lower stripper plates 65 are moved upward by the springs 66 to move the strips 21a slightly upward to push the tabs 86 out of the punch receiving apertures in the dies plates 5|, 52 and 53. Simultaneously with the stitching operation the shearing die I4 on each operation thereof shears the strips 21a transversely thereof and shears off two sectionally constructed blanks which are in the shape of a trapezoid, each blank comprising a plurality of attached together pieces of the strips 21a as shown in Fig. 14. Preferably the press for operating the stitching and shearing dies is of the type which is automatically and periodically tripped. After the blanks are sheared off from the strips they may be formed by suitable dies into spring casings of the character shown in Figures 15 and 16. In the first forming operation the blankxis bent along one longitudinal edge thereof providing the outturned flange I23 having the offset portion I25 bent back upon itself and in the second operation, the blank is bent along theother longitudinal edge thereof providing the flange I24. In the third :forming operation the blank is bent along a line spaced inwardly of the flange I23 providing the top casing wall I29 and a crimped offset portion I29a which offset portion IZSJa .provides for taking up slack in fitting the casing over a leaf spring. In the final operation, the blank is bent along two lines longitudinally of the blank providing the bottom and side walls I 32 and I33 respectively, of the finished casing. The flanges I 24, I25 are adapted for interlocking relation to close the casing after it is positioned or fitted over .a leaf spring.

By the present method of preparing blanks wherein a plurality of metallic strips are automatically fed, attached together and then sheared into sectionally constructed :blanks, these blanks may be easily and conveniently handled to form an elongated longitudinally flexible leaf spring casing. Moreover longitudinal flexible spring casings are not only easily and eiflciently manufactured from the blanks made by the herein disclosed method but are strong and durable and maybe inexpensively manufactured.

What I claim is:

1. The method of preparing sectionally constructed blanks for manufacturing flexible casings for leaf springs which comprises, attaching together side-by-side a plurality of continuous strips of relatively great lengths in proportion to their widths along adjacent longitudinal edges thereof 'at predetermined longitudinally spaced locations therealong, said strips being free from such attachment between said locations, whereby to permit relativemotion therebetween in response to the flexing of the spring, and then shearing the strips transversely thereof into blanks each comprising a plurality of attached together pieces of the strips.

2. The method of preparing sectionally constructed blanks for manufacturing flexible casings which comprises, feeding a plurality of juxtapositioned continuous strips of relatively great lengths in proportion to their widths in side-byside substantially parallel relation, attaching adjacent strips together at predetermined longitudinally spaced locations therealong, said strips being free from such attachment between said locations, whereby to permit relative mo .tion therebetween in response to .the flexing of the spring, and then shearing the strips itransversely thereof into sectionally constructed blanks comprising attached together pieces of the strips.

3. The method of preparing blanks for manufacturing sectionally constructed flexible covers for leaf springs which comprises, feeding a plurality of metallic strips of relatively great lengths ,inproportion to their widths in side-byside longitudinal relation, guiding the strips so that adjacent longitudinal border portions thereof are in relative overlapping relation, attaching the strips together at and along the overlapping portions thereofat predetermined longitudinally spaced locations therealong, saidstrips being free from such attachment between said locations, whereby to permit relative motion therebetween in response to the flexing of the spring, and then shearing the strips transversely thereof into blanks each comprising a plurality of attached .together pieces of the strips.

4. The method of preparing sectionally constructed blanks for manufacturing elongated longitudinally flexible covers for leaf springs which comprises, intermittently feeding continuous metallic strips in relative longitudinal relation, guiding the strips so that adjacent edges of adjacent strips are in relative overlapping relation as the strips are fed, attaching the overlapping portions together at spaced intervals therealong by mutually forming out and bending over tabs from the overlapped portions, and then simultaneously shearing the strips transversely thereof into trapezoidal blanks comprising attached together pieces of the strips.

5. The method of preparing sectionally constructed blanks for manufacturing elongated longitudinally flexible covers for leaf springs which method comprises, feeding continuous narrow strips of relatively great lengths in proportion to their widths in side-by-side longitudinal relation, guiding the strips so that adjacent longitudinal border portions thereof are in relatively overlapping relation as the strips are fed, attaching the overlapping border portions together at predetermined longitudinally spaced locations therealong, said overlapping border portions being free from such attachment between said locations whereby to permit relative motion therebetween in response to the flexing of the spring, and then shearing the strips transversely thereof into blanks comprising attached together pieces of the strips.

CHARLES B. EISENHAUER. 

